First time trip in early September

my fiance and I, along with two of our friends will be heading out on our very first road trip august 31st for my birthday. it is something him and i have wanted to do since we were kids. our plan is to drive from Orlando, FL to Nashville, TN then from there to New Orleans, LA before heading back home. now since none of us have done this before i was wondering if anyone had any tips or knew any where that we should stop along the way to see? we will be going through all the states in the southeast.
thanks!
Melissa